The scaphoid cortical ring sign is produced by the foreshortened appearance of the distal pole of the scaphoid rotated on its axis by scapholunate dissociation, one of the manifestations of carpal instability syndromes

It may, however, be present normally and should be evaluated in light of clinical findings

Normally, the distance between the scaphoid and the lunate is < 3 mm in the frontal view

Scaphoid Cortical Ring Sign. When there is rotation of the scaphoid as can occur with scapholunate dissociation (widening of distance between scaphoid and lunate to greater than 3 mm), (yellow arrow), a ring-shaped density can appear as a sign of foreshortening (white arrow).
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